In digital imaging systems, color management is the controlled conversion between the color representations of various devices, such as image scanners, digital cameras, monitors, TV screens, film printers, marking devices, offset presses, and corresponding media. One of the primary goals of color management is to obtain a good match across color devices; for example, a video which should appear the same color on a computer LCD monitor, a plasma TV screen, and on a printed frame of video. Mapping of color spaces to the target color points of different target devices is used since many devices do not have the same gamut, or range of colors and brightness, that they are able to produce. For example, some colors outside of a target device's gamut need to be carefully mapped to the surface or inside of the gamut as they otherwise cannot be represented on the output device and would simply be clipped to some undesirable point on the gamut. Color mapping functions are used to adjust the numerical values that are sent to, or received from, different devices so that the perceived color they produce remains consistent. Such color mapping is often performed during profile creation. Standardizing run-time custom profiling code becomes difficult to achieve as no single unique gamut mapping strategy is able to be applied to color space which simultaneously satisfies all requirements such as pleasing color, contrast, lightness, chroma, hue, and the like, across all out-of gamut color points.
Methods have been developed for retrieving or otherwise reverse-engineering color gamut mapping rays from an original ICC profile so that the same gamut mapping can be incorporated in custom destination profiles during runtime. However, the shapes of the gamuts between two devices may vary substantially. These variations may be due to different curvatures of the gamut surface custom made by different toners/inks. If the shapes of the gamuts of the seed and host devices are substantially different, the gamut mapping vectors can either completely miss the surface of the host gamut or intersect the host gamut at an erroneous location, thus producing false gamut mapping rays which may lead to pathological results such as to color contours arising in the output print. False gamut mapping rays need to be automatically compensated for without a user intervention.
Accordingly, what is needed in this art is a method for mapping out-of-gamut colors of a device to its gamut by using the gamut mapping strategy of another device as a reference which accounts for those instances wherein the shapes of the two gamuts are substantially different.